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1   ///////////////////////////////////////////////////////////////////////////////////////////////
2   // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3   // Copyright (C) 2001-2024 the original author or authors.
4   //
5   // This library is free software; you can redistribute it and/or
6   // modify it under the terms of the GNU Lesser General Public
7   // License as published by the Free Software Foundation; either
8   // version 2.1 of the License, or (at your option) any later version.
9   //
10  // This library is distributed in the hope that it will be useful,
11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  // Lesser General Public License for more details.
14  //
15  // You should have received a copy of the GNU Lesser General Public
16  // License along with this library; if not, write to the Free Software
17  // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  ///////////////////////////////////////////////////////////////////////////////////////////////
19  
20  package com.puppycrawl.tools.checkstyle;
21  
22  import java.beans.PropertyDescriptor;
23  import java.lang.reflect.InvocationTargetException;
24  import java.net.URI;
25  import java.util.ArrayList;
26  import java.util.Collection;
27  import java.util.List;
28  import java.util.Locale;
29  import java.util.StringTokenizer;
30  import java.util.regex.Pattern;
31  
32  import javax.annotation.Nullable;
33  
34  import org.apache.commons.beanutils.BeanUtilsBean;
35  import org.apache.commons.beanutils.ConversionException;
36  import org.apache.commons.beanutils.ConvertUtilsBean;
37  import org.apache.commons.beanutils.Converter;
38  import org.apache.commons.beanutils.PropertyUtils;
39  import org.apache.commons.beanutils.PropertyUtilsBean;
40  import org.apache.commons.beanutils.converters.ArrayConverter;
41  import org.apache.commons.beanutils.converters.BooleanConverter;
42  import org.apache.commons.beanutils.converters.ByteConverter;
43  import org.apache.commons.beanutils.converters.CharacterConverter;
44  import org.apache.commons.beanutils.converters.DoubleConverter;
45  import org.apache.commons.beanutils.converters.FloatConverter;
46  import org.apache.commons.beanutils.converters.IntegerConverter;
47  import org.apache.commons.beanutils.converters.LongConverter;
48  import org.apache.commons.beanutils.converters.ShortConverter;
49  
50  import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
51  import com.puppycrawl.tools.checkstyle.api.Configurable;
52  import com.puppycrawl.tools.checkstyle.api.Configuration;
53  import com.puppycrawl.tools.checkstyle.api.Context;
54  import com.puppycrawl.tools.checkstyle.api.Contextualizable;
55  import com.puppycrawl.tools.checkstyle.api.Scope;
56  import com.puppycrawl.tools.checkstyle.api.SeverityLevel;
57  import com.puppycrawl.tools.checkstyle.checks.naming.AccessModifierOption;
58  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
59  
60  /**
61   * A Java Bean that implements the component lifecycle interfaces by
62   * calling the bean's setters for all configuration attributes.
63   */
64  public abstract class AbstractAutomaticBean
65      implements Configurable, Contextualizable {
66  
67      /**
68       * Enum to specify behaviour regarding ignored modules.
69       */
70      public enum OutputStreamOptions {
71  
72          /**
73           * Close stream in the end.
74           */
75          CLOSE,
76  
77          /**
78           * Do nothing in the end.
79           */
80          NONE,
81  
82      }
83  
84      /** Comma separator for StringTokenizer. */
85      private static final String COMMA_SEPARATOR = ",";
86  
87      /** The configuration of this bean. */
88      private Configuration configuration;
89  
90      /**
91       * Provides a hook to finish the part of this component's setup that
92       * was not handled by the bean introspection.
93       * <p>
94       * The default implementation does nothing.
95       * </p>
96       *
97       * @throws CheckstyleException if there is a configuration error.
98       */
99      protected abstract void finishLocalSetup() throws CheckstyleException;
100 
101     /**
102      * Creates a BeanUtilsBean that is configured to use
103      * type converters that throw a ConversionException
104      * instead of using the default value when something
105      * goes wrong.
106      *
107      * @return a configured BeanUtilsBean
108      */
109     private static BeanUtilsBean createBeanUtilsBean() {
110         final ConvertUtilsBean cub = new ConvertUtilsBean();
111 
112         registerIntegralTypes(cub);
113         registerCustomTypes(cub);
114 
115         return new BeanUtilsBean(cub, new PropertyUtilsBean());
116     }
117 
118     /**
119      * Register basic types of JDK like boolean, int, and String to use with BeanUtils. All these
120      * types are found in the {@code java.lang} package.
121      *
122      * @param cub
123      *            Instance of {@link ConvertUtilsBean} to register types with.
124      */
125     private static void registerIntegralTypes(ConvertUtilsBean cub) {
126         cub.register(new BooleanConverter(), Boolean.TYPE);
127         cub.register(new BooleanConverter(), Boolean.class);
128         cub.register(new ArrayConverter(
129             boolean[].class, new BooleanConverter()), boolean[].class);
130         cub.register(new ByteConverter(), Byte.TYPE);
131         cub.register(new ByteConverter(), Byte.class);
132         cub.register(new ArrayConverter(byte[].class, new ByteConverter()),
133             byte[].class);
134         cub.register(new CharacterConverter(), Character.TYPE);
135         cub.register(new CharacterConverter(), Character.class);
136         cub.register(new ArrayConverter(char[].class, new CharacterConverter()),
137             char[].class);
138         cub.register(new DoubleConverter(), Double.TYPE);
139         cub.register(new DoubleConverter(), Double.class);
140         cub.register(new ArrayConverter(double[].class, new DoubleConverter()),
141             double[].class);
142         cub.register(new FloatConverter(), Float.TYPE);
143         cub.register(new FloatConverter(), Float.class);
144         cub.register(new ArrayConverter(float[].class, new FloatConverter()),
145             float[].class);
146         cub.register(new IntegerConverter(), Integer.TYPE);
147         cub.register(new IntegerConverter(), Integer.class);
148         cub.register(new ArrayConverter(int[].class, new IntegerConverter()),
149             int[].class);
150         cub.register(new LongConverter(), Long.TYPE);
151         cub.register(new LongConverter(), Long.class);
152         cub.register(new ArrayConverter(long[].class, new LongConverter()),
153             long[].class);
154         cub.register(new ShortConverter(), Short.TYPE);
155         cub.register(new ShortConverter(), Short.class);
156         cub.register(new ArrayConverter(short[].class, new ShortConverter()),
157             short[].class);
158         cub.register(new RelaxedStringArrayConverter(), String[].class);
159 
160         // BigDecimal, BigInteger, Class, Date, String, Time, TimeStamp
161         // do not use defaults in the default configuration of ConvertUtilsBean
162     }
163 
164     /**
165      * Register custom types of JDK like URI and Checkstyle specific classes to use with BeanUtils.
166      * None of these types should be found in the {@code java.lang} package.
167      *
168      * @param cub
169      *            Instance of {@link ConvertUtilsBean} to register types with.
170      */
171     private static void registerCustomTypes(ConvertUtilsBean cub) {
172         cub.register(new PatternConverter(), Pattern.class);
173         cub.register(new SeverityLevelConverter(), SeverityLevel.class);
174         cub.register(new ScopeConverter(), Scope.class);
175         cub.register(new UriConverter(), URI.class);
176         cub.register(new RelaxedAccessModifierArrayConverter(), AccessModifierOption[].class);
177     }
178 
179     /**
180      * Implements the Configurable interface using bean introspection.
181      *
182      * <p>Subclasses are allowed to add behaviour. After the bean
183      * based setup has completed first the method
184      * {@link #finishLocalSetup finishLocalSetup}
185      * is called to allow completion of the bean's local setup,
186      * after that the method {@link #setupChild setupChild}
187      * is called for each {@link Configuration#getChildren child Configuration}
188      * of {@code configuration}.
189      *
190      * @see Configurable
191      */
192     @Override
193     public final void configure(Configuration config)
194             throws CheckstyleException {
195         configuration = config;
196 
197         final String[] attributes = config.getPropertyNames();
198 
199         for (final String key : attributes) {
200             final String value = config.getProperty(key);
201 
202             tryCopyProperty(key, value, true);
203         }
204 
205         finishLocalSetup();
206 
207         final Configuration[] childConfigs = config.getChildren();
208         for (final Configuration childConfig : childConfigs) {
209             setupChild(childConfig);
210         }
211     }
212 
213     /**
214      * Recheck property and try to copy it.
215      *
216      * @param key key of value
217      * @param value value
218      * @param recheck whether to check for property existence before copy
219      * @throws CheckstyleException when property defined incorrectly
220      */
221     private void tryCopyProperty(String key, Object value, boolean recheck)
222             throws CheckstyleException {
223         final BeanUtilsBean beanUtils = createBeanUtilsBean();
224 
225         try {
226             if (recheck) {
227                 // BeanUtilsBean.copyProperties silently ignores missing setters
228                 // for key, so we have to go through great lengths here to
229                 // figure out if the bean property really exists.
230                 final PropertyDescriptor descriptor =
231                         PropertyUtils.getPropertyDescriptor(this, key);
232                 if (descriptor == null) {
233                     final String message = String.format(Locale.ROOT, "Property '%s' "
234                             + "does not exist, please check the documentation", key);
235                     throw new CheckstyleException(message);
236                 }
237             }
238             // finally we can set the bean property
239             beanUtils.copyProperty(this, key, value);
240         }
241         catch (final InvocationTargetException | IllegalAccessException
242                 | NoSuchMethodException ex) {
243             // There is no way to catch IllegalAccessException | NoSuchMethodException
244             // as we do PropertyUtils.getPropertyDescriptor before beanUtils.copyProperty,
245             // so we have to join these exceptions with InvocationTargetException
246             // to satisfy UTs coverage
247             final String message = String.format(Locale.ROOT,
248                     "Cannot set property '%s' to '%s'", key, value);
249             throw new CheckstyleException(message, ex);
250         }
251         catch (final IllegalArgumentException | ConversionException ex) {
252             final String message = String.format(Locale.ROOT, "illegal value '%s' for property "
253                     + "'%s'", value, key);
254             throw new CheckstyleException(message, ex);
255         }
256     }
257 
258     /**
259      * Implements the Contextualizable interface using bean introspection.
260      *
261      * @see Contextualizable
262      */
263     @Override
264     public final void contextualize(Context context)
265             throws CheckstyleException {
266         final Collection<String> attributes = context.getAttributeNames();
267 
268         for (final String key : attributes) {
269             final Object value = context.get(key);
270 
271             tryCopyProperty(key, value, false);
272         }
273     }
274 
275     /**
276      * Returns the configuration that was used to configure this component.
277      *
278      * @return the configuration that was used to configure this component.
279      */
280     protected final Configuration getConfiguration() {
281         return configuration;
282     }
283 
284     /**
285      * Called by configure() for every child of this component's Configuration.
286      * <p>
287      * The default implementation throws {@link CheckstyleException} if
288      * {@code childConf} is {@code null} because it doesn't support children. It
289      * must be overridden to validate and support children that are wanted.
290      * </p>
291      *
292      * @param childConf a child of this component's Configuration
293      * @throws CheckstyleException if there is a configuration error.
294      * @see Configuration#getChildren
295      */
296     protected void setupChild(Configuration childConf)
297             throws CheckstyleException {
298         if (childConf != null) {
299             throw new CheckstyleException(childConf.getName() + " is not allowed as a child in "
300                     + configuration.getName() + ". Please review 'Parent Module' section "
301                     + "for this Check in web documentation if Check is standard.");
302         }
303     }
304 
305     /** A converter that converts a string to a pattern. */
306     private static final class PatternConverter implements Converter {
307 
308         @SuppressWarnings("unchecked")
309         @Override
310         public Object convert(Class type, Object value) {
311             return CommonUtil.createPattern(value.toString());
312         }
313 
314     }
315 
316     /** A converter that converts strings to severity level. */
317     private static final class SeverityLevelConverter implements Converter {
318 
319         @SuppressWarnings("unchecked")
320         @Override
321         public Object convert(Class type, Object value) {
322             return SeverityLevel.getInstance(value.toString());
323         }
324 
325     }
326 
327     /** A converter that converts strings to scope. */
328     private static final class ScopeConverter implements Converter {
329 
330         @SuppressWarnings("unchecked")
331         @Override
332         public Object convert(Class type, Object value) {
333             return Scope.getInstance(value.toString());
334         }
335 
336     }
337 
338     /** A converter that converts strings to uri. */
339     private static final class UriConverter implements Converter {
340 
341         @SuppressWarnings("unchecked")
342         @Override
343         @Nullable
344         public Object convert(Class type, Object value) {
345             final String url = value.toString();
346             URI result = null;
347 
348             if (!CommonUtil.isBlank(url)) {
349                 try {
350                     result = CommonUtil.getUriByFilename(url);
351                 }
352                 catch (CheckstyleException ex) {
353                     throw new IllegalArgumentException(ex);
354                 }
355             }
356 
357             return result;
358         }
359 
360     }
361 
362     /**
363      * A converter that does not care whether the array elements contain String
364      * characters like '*' or '_'. The normal ArrayConverter class has problems
365      * with these characters.
366      */
367     private static final class RelaxedStringArrayConverter implements Converter {
368 
369         @SuppressWarnings("unchecked")
370         @Override
371         public Object convert(Class type, Object value) {
372             final StringTokenizer tokenizer = new StringTokenizer(
373                 value.toString().trim(), COMMA_SEPARATOR);
374             final List<String> result = new ArrayList<>();
375 
376             while (tokenizer.hasMoreTokens()) {
377                 final String token = tokenizer.nextToken();
378                 result.add(token.trim());
379             }
380 
381             return result.toArray(CommonUtil.EMPTY_STRING_ARRAY);
382         }
383 
384     }
385 
386     /**
387      * A converter that converts strings to {@link AccessModifierOption}.
388      * This implementation does not care whether the array elements contain characters like '_'.
389      * The normal {@link ArrayConverter} class has problems with this character.
390      */
391     private static final class RelaxedAccessModifierArrayConverter implements Converter {
392 
393         /** Constant for optimization. */
394         private static final AccessModifierOption[] EMPTY_MODIFIER_ARRAY =
395                 new AccessModifierOption[0];
396 
397         @SuppressWarnings("unchecked")
398         @Override
399         public Object convert(Class type, Object value) {
400             // Converts to a String and trims it for the tokenizer.
401             final StringTokenizer tokenizer = new StringTokenizer(
402                 value.toString().trim(), COMMA_SEPARATOR);
403             final List<AccessModifierOption> result = new ArrayList<>();
404 
405             while (tokenizer.hasMoreTokens()) {
406                 final String token = tokenizer.nextToken();
407                 result.add(AccessModifierOption.getInstance(token));
408             }
409 
410             return result.toArray(EMPTY_MODIFIER_ARRAY);
411         }
412 
413     }
414 
415 }